fix(installer): fall back when brew install fails (#2881)

scripts/install.sh

@@ -66,16 +66,27 @@ detect_os() {
 install_cli_brew() {
   info "Installing Multica CLI via Homebrew..."
   if ! brew tap multica-ai/tap 2>/dev/null; then
-    fail "Failed to add Homebrew tap. Check your network connection."
+    warn "Failed to add Homebrew tap. Falling back to GitHub Releases binary install."
+    return 1
   fi
   # brew install exits non-zero if already installed on older Homebrew versions
-  if ! brew install "$BREW_PACKAGE" 2>/dev/null; then
+  local brew_log
+  brew_log=$(mktemp)
+  if ! brew install "$BREW_PACKAGE" >"$brew_log" 2>&1; then
     if brew list "$BREW_PACKAGE" >/dev/null 2>&1; then
+      rm -f "$brew_log"
       ok "Multica CLI already installed via Homebrew"
     else
-      fail "Failed to install multica via Homebrew."
+      warn "Failed to install multica via Homebrew. Falling back to GitHub Releases binary install."
+      if [ -s "$brew_log" ]; then
+        warn "Homebrew output (last 80 lines):"
+        tail -n 80 "$brew_log" | sed 's/^/  /' >&2
+      fi
+      rm -f "$brew_log"
+      return 1
     fi
   else
+    rm -f "$brew_log"
     ok "Multica CLI installed via Homebrew"
   fi
 }
@@ -103,8 +114,9 @@ install_cli_binary() {
 
   tar -xzf "$tmp_dir/multica.tar.gz" -C "$tmp_dir" multica
 
-  # Try /usr/local/bin first, fall back to ~/.local/bin
-  local bin_dir="/usr/local/bin"
+  # Try /usr/local/bin first, fall back to ~/.local/bin. Tests and scripted
+  # installs can override the first choice with MULTICA_BIN_DIR.
+  local bin_dir="${MULTICA_BIN_DIR:-/usr/local/bin}"
   if [ -w "$bin_dir" ]; then
     mv "$tmp_dir/multica" "$bin_dir/multica"
   elif command_exists sudo; then
@@ -232,7 +244,7 @@ install_cli() {
   fi
 
   if command_exists brew; then
-    install_cli_brew
+    install_cli_brew || install_cli_binary
   else
     install_cli_binary
   fi

scripts/install.test.sh

@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+test_brew_failure_falls_back_to_release_binary() {
+  local tmp
+  tmp="$(mktemp -d)"
+  trap 'rm -rf "$tmp"' RETURN
+
+  local stub_bin="$tmp/stub-bin"
+  local install_bin="$tmp/install-bin"
+  local payload_dir="$tmp/payload"
+  mkdir -p "$stub_bin" "$install_bin" "$payload_dir"
+
+  cat >"$stub_bin/brew" <<'STUB'
+#!/usr/bin/env bash
+case "${1:-}" in
+  tap)
+    exit 0
+    ;;
+  install)
+    echo "simulated brew install failure" >&2
+    exit 42
+    ;;
+  list)
+    exit 1
+    ;;
+  *)
+    exit 0
+    ;;
+esac
+STUB
+  chmod +x "$stub_bin/brew"
+
+  cat >"$payload_dir/multica" <<'STUB'
+#!/usr/bin/env bash
+echo "multica v0.3.2 (commit: test)"
+STUB
+  chmod +x "$payload_dir/multica"
+  tar -czf "$tmp/multica.tar.gz" -C "$payload_dir" multica
+
+  cat >"$stub_bin/curl" <<'STUB'
+#!/usr/bin/env bash
+if [[ "$*" == *"-sI"* ]]; then
+  printf 'HTTP/2 302\r\nlocation: https://github.com/multica-ai/multica/releases/tag/v0.3.2\r\n'
+  exit 0
+fi
+
+out=""
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    -o)
+      out="$2"
+      shift 2
+      ;;
+    *)
+      shift
+      ;;
+  esac
+done
+
+if [[ -z "$out" ]]; then
+  echo "stub curl expected -o" >&2
+  exit 2
+fi
+cp "$MULTICA_TEST_ARCHIVE" "$out"
+STUB
+  chmod +x "$stub_bin/curl"
+
+  local out="$tmp/install.out"
+  local err="$tmp/install.err"
+  if ! PATH="$stub_bin:$install_bin:/usr/bin:/bin" \
+    MULTICA_BIN_DIR="$install_bin" \
+    MULTICA_TEST_ARCHIVE="$tmp/multica.tar.gz" \
+    bash "$ROOT_DIR/scripts/install.sh" >"$out" 2>"$err"; then
+    echo "expected install.sh to fall back after brew install failure" >&2
+    cat "$out" >&2 || true
+    cat "$err" >&2 || true
+    return 1
+  fi
+
+  if [[ ! -x "$install_bin/multica" ]]; then
+    echo "expected fallback binary at $install_bin/multica" >&2
+    cat "$out" >&2 || true
+    cat "$err" >&2 || true
+    return 1
+  fi
+}
+
+test_brew_failure_falls_back_to_release_binary
+echo "install.sh tests passed"